Integrating Species Mixtures in Tree Growth Functions for Forest Development Models in Switzerland (Swiss-SpeMixMod)

The main objective of this project is to investigate methodologies for quantifying the effects of species mixtures on tree growth along Switzerland's environmental gradients, and to prepare this knowledge for the use in forest scenario calculations. The project comprises of three major parts: (1) a systematic, descriptive analysis of data from the Swiss National Forest Inventory (NFI) to provide an overview of the frequency and the distribution of pure and mixed forests in Switzerland; (2) quantification of mixing effects with nonlinear mixed-effect models fitted to NFI data and their variability with climatic, edaphic, stand and site conditions, as well as with species composition, across Switzerland's environmental gradient; (3) identification of the different modes of intra- and inter-specific interactions using competition indices in Swiss mixed-species forests and their integration in growth functions.